The sooty falcon is one of only six species of completely migratory birds of prey worldwide that breed in the northern hemisphere and overwinter in the southern hemisphere (11). Although sooty falcons begin to arrive at their breeding locations in the spring, around late April, they do not commence breeding until late summer (9). This delay occurs so that chick-rearing coincides with the autumn migration of small birds from cooler temperate regions in the North, which provide an abundance of food for the sooty falcon chicks (6) (12). A specialist in migratory bird hunting, the sooty falcon is generally most active at dusk and dawn, when solitary individuals can be seen perched on rocks or vegetation, scanning the sky for passing migrant birds. When a bird flies overhead, the sooty falcon rapidly takes to the air, accelerating above its prey before making a low dive and seizing it in its talons (12). Species taken include the hoopoe (Upupa epops), the European bee eater (Merops apiaster) and a variety of warblers (2) (7).
During the breeding season, sooty falcons form breeding pairs which either nest alone or in loose colonies of up to 100 pairs (12). The female lays up to four eggs in a scraped out hollow in the ground or amongst rocks, which in the summer heat may be exposed to temperatures of around 50 degrees Celsius. After around a month, despite the extreme conditions, the majority of sooty falcon eggs hatch successfully (6) (7).
The breeding season ends in late October, and the adults and juveniles begin the long journey to the wintering grounds in Madagascar and southern Africa (7) (9). Here, the sooty falcon mainly subsists on large insects, but also bats and small birds (4) (5). Until recently, the route taken by the sooty falcon on its migratory journey was unclear, but in 2008, the Environment Agency – Abu Dhabi (EAD) successfully tracked a single sooty falcon from its nest on an island in the Sila Peninsula, Abu Dhabi to Madagascar. Using satellite tracking, the study revealed that the bird flew through seven countries, covering an incredible 6,700 kilometres (9) (13).